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Posted: Wed Feb 11, 2009 10:57 pm
by redmondjp
Hi Noah,

The best way to check the cables is to measure the voltage drop across the cable while the starter is engaged. Put your voltmeter on a low-volt range (say, 3V or whatever range is close), and put one meter lead at each end of the cable (jamb probe between insulation and the copper strands, that usually works).

Then have a helper crank the starter and see what the voltage drop across the cable is. Ideally you want zero, but realistically, you should see much less than a volt drop per each cable section, say less than 0.5V.

You can also measure the battery voltage directly across the battery while cranking (probably between 9-11 volts), and then move the positive meter lead down to the terminal right on the starter (also while cranking) and then subtract the two readings--the difference is the voltage drop across your battery cable.

As you found out while the starter was stuck (did it short out? Kind of sounds like it may have), cables can get really hot, especially if there are any high-resistance spots such as the crimps on the ends.

On my SD22, I put beefy battery cables on it, I think they were 2 gauge copper. The stock ground cable was, putting it nicely, crap! You want the ground cable going right from the battery to somewhere on the engine (I used a bellhousing bolt on the right side of the engine) to minimize the resistance in the circuit.

And if you don't have a voltmeter to test the cables, just use your hand and check for hot spots. If you crank for 5-10 seconds and then stop, you should be able to hold your hand along any point on the wires. If you can't--there is a problem, too much resistance.

HTH! :D

Posted: Wed Feb 11, 2009 11:24 pm
by kassim503
ocd wrote:pulled the ground cable where the smoke was coming from and it was crispy so i made a new one with some fat cable soldered into copper ring terminals and heat shrink tubing
I think your not supposed to solder the ends onto the cables, its supposed to be b/c under heavy cranking/ current overdraw situations where the wire may heat up past the solders boiling point and lead to a failed/ drippy connector that might start a fire or drop the wire onto a ground plane. They are supposed to be crimped together with some tool, forgot the name for the whole process though.

Not saying you cant, if you are cranking and the connectors stay cold, it'll be fine. But the 6.2 starter can definitely draw some amps

Posted: Sat Feb 14, 2009 1:01 am
by redmondjp
kassim,

The biggest reason they don't want you to solder the ends is that the solder can wick up into the wire and make it stiff, and then this can cause fatigue of the copper (basically a stress point) right at the point where the solder ends up inside the wire.

If your battery cable or its ends get hot enough to melt solder (basically almost 500 degrees F), you've got serious problems!

I have soldered battery cable ends before, and it's not a problem if done properly.

Posted: Sat Feb 14, 2009 5:08 pm
by kassim503
oh, well in that case ill be soldering my own battery cables up the next time the opportunity rises.

Ive seen damaged cables spark upon start up, so I figured that would be the reason everybody is swedging (<-remembered name!) cables up

Posted: Sun Feb 22, 2009 8:22 pm
by asavage
You folks kinda took over my thread while I was away!

The rubber plugs do not last, but you can get a couple/few years from them. I put one in my grey '89 Aero in 1999, it began leaking about three years later, put in another, it leaked in 2006, now on third one.

I love my Dremels (I own three of 'em) but I'd be very very careful using one on this job, it's all too easy to end up with a nicked bore and you're not supposed to use sealant on the OD of the replacement casting plug (they're not really freeze plugs, folks; they are not at all designed as protection from not running anti-freeze).

I was at a JY yesterday, there were FIVE 6.2l trucks there, three still with complete engines! That's quite rare around here. Two still had intake mufflers, and Mark bought two of the older, firewall-mounted fuel filter bases with top bleed screw, for $5 each. They take the Wix/NAPA 33123 filter with the drain valve that comes with the filter.

Posted: Mon Feb 23, 2009 11:13 pm
by ocd
i keep thinking about a swap of a 6.2l into some J body car with decent aerodynamics. apparently the 6.2 has the same mounts as a SB 350. that would be a fun car with excellent fuel economy.